fix(spawn): sanitize claudecode in shared claude env builders

- strip CLAUDECODE from cliproxy-built Claude environments

- enforce sanitization in ClaudeAdapter buildEnv

- apply same env hardening in shared spawnClaude helper

Refs #588

src/cliproxy/executor/env-resolver.ts

@@ -20,6 +20,7 @@ import { CLIProxyProvider } from '../types';
 import { CompositeTierConfig } from '../../config/unified-config-types';
 import { getWebSearchHookEnv } from '../../utils/websearch-manager';
 import { getImageAnalysisHookEnv } from '../../utils/hooks/get-image-analysis-hook-env';
+import { stripClaudeCodeEnv } from '../../utils/shell-executor';
 import { CodexReasoningProxy } from '../codex-reasoning-proxy';
 import { ToolSanitizationProxy } from '../tool-sanitization-proxy';
 import { HttpsTunnelProxy } from '../https-tunnel-proxy';
@@ -219,13 +220,17 @@ export function buildClaudeEnvironment(config: ProxyChainConfig): Record<string,
     Object.entries(effectiveEnvVars).filter(([, v]) => v !== undefined)
   ) as Record<string, string>;
 
-  return {
+  const mergedEnv = {
     ...baseEnv,
     ...effectiveEnvVarsFiltered,
     ...webSearchEnv,
     ...imageAnalysisEnv,
     CCS_PROFILE_TYPE: 'cliproxy', // Signal to WebSearch hook this is a third-party provider
   };
+
+  return Object.fromEntries(
+    Object.entries(stripClaudeCodeEnv(mergedEnv)).filter(([, v]) => v !== undefined)
+  ) as Record<string, string>;
 }
 
 /**

src/targets/claude-adapter.ts

@@ -9,7 +9,7 @@ import { spawn, ChildProcess } from 'child_process';
 import { TargetAdapter, TargetBinaryInfo, TargetCredentials, TargetType } from './target-adapter';
 import { detectClaudeCli, getClaudeCliInfo } from '../utils/claude-detector';
 import type { ProfileType } from '../types/profile';
-import { escapeShellArg, stripAnthropicEnv } from '../utils/shell-executor';
+import { escapeShellArg, stripAnthropicEnv, stripClaudeCodeEnv } from '../utils/shell-executor';
 import { ErrorManager } from '../utils/error-manager';
 import { getWebSearchHookEnv } from '../utils/websearch-manager';
 import { wireChildProcessSignals } from '../utils/signal-forwarder';
@@ -56,7 +56,7 @@ export class ClaudeAdapter implements TargetAdapter {
     if (creds.apiKey) env['ANTHROPIC_AUTH_TOKEN'] = creds.apiKey;
     if (creds.model) env['ANTHROPIC_MODEL'] = creds.model;
 
-    return env;
+    return stripClaudeCodeEnv(env);
   }
 
   exec(

src/utils/claude-spawner.ts

@@ -6,7 +6,7 @@
  */
 
 import { spawn, ChildProcess, SpawnOptions } from 'child_process';
-import { escapeShellArg } from './shell-executor';
+import { escapeShellArg, stripClaudeCodeEnv } from './shell-executor';
 import { getClaudeCliInfo } from './claude-detector';
 import { ErrorManager } from './error-manager';
 
@@ -46,7 +46,8 @@ export function spawnClaude(options: SpawnClaudeOptions = {}): SpawnClaudeResult
   const { args = [], env, cwd, stdio = 'inherit' } = options;
 
   // Merge environment
-  const mergedEnv = env ? { ...process.env, ...env } : process.env;
+  const mergedEnvBase = env ? { ...process.env, ...env } : process.env;
+  const mergedEnv = stripClaudeCodeEnv(mergedEnvBase);
 
   let child: ChildProcess;
   if (needsShell) {